Question

Dan are un nr de bacnote de cate 5 lei.Ion are acelasi nr de bacnote de cate 10 leiCati lei are fiecare daca Ion are cu 40 de lei mai mult decat Dan?

Answer 1

5xa=c 10xa=40+c 5xa+10xa=40+2xc 2xa+10+5=40+2xc

Answer 2

 x= nr. de bacnote
10x = banii pe care ii are Ion
5x = Banii pe care ii are Dan

5x + 40= 10x  |-5x
5x-5x+40=10x-5x
40=5x | :5
x=8 
=> Dan are : 5x=5*8 = 40 
=> Ion are : 10x = 10*8 = 80

Deci... Dan are 40 de lei , iar Ion are 80 de lei .